This invention relates generally to a log transport and sawing system for breaking a substantially cylindrical log into a plurality of individual elongated pieces. More particularly, it relates to an end dogging and axial transport system for moving logs past a plurality of angularly disposed saws for dividing the log into a plurality of elongated sector-shaped pieces.
The art of quarter sawing is well known and is utilized in the hardwood lumber and veneer manufacturing industry. To quarter saw a log, a log is mounted in a suitable holding device and is then sawn into sector-shaped pieces with a normal angle between radial faces being on the order of 90.degree.. One typical means for quartering a log is simply to mount the log in a well-known carriage and pass it by a vertically disposed band saw where it is halved. Each individual half is then mounted on a similar carriage and passed by a similar band saw where it is quartered. The quarter sectors are then sawn into lumber or sliced into veneers. This process is time consuming and also has a tendency to produce irregular quarter sectors since several passes past a saw are required in order to produce the quarter sectors.
In the log cutting and rejoining process that is described in U.S. Pat. No. 3,961,654 which is assigned to assignee of the present invention, a process is disclosed whereby relatively small logs are sawn or otherwise divided into a plurality of individual elongated sector-shaped pieces and then rejoined into parallelograms thin edge to thick edge. As is disclosed within the patent, one of the first steps in the manufacturing process is to substantially quarter a log. The disclosure indicates that any known quarter sawing process could be utilized for producing substantially quarter sectors from the logs. Based on production requirements, it has been determined that the known processes and systems for quartering a log are slow and tend to yield sector-shaped pieces, as previously noted, that are nonuniform and which would tend to be unsuitable for use in the process of U.S. Pat. No. 3,961,654. Thus a log transport and quarter sawing system that produces substantially quarter elongated sector-shaped pieces at suitable production speeds and with the required degree of uniformity in size is required for efficiently practicing the aforementioned process.
Accordingly, from the foregoing, one object of the present invention is to provide a transport system for sawing logs that both positions and accurately transports the log through a predetermined path of travel.
Another object of this invention is to securely hold the log in its prealigned position as it is being transported through a sawing station.
Still a further object of this invention is to provide a sawing station that produces a plurality of individual elongated sector-shaped pieces substantially simultaneously from the same log.
Yet another object of this invention is to provide a sawing station comprised of a plurality of saws whereby the angular relationships between at least some of the saws may be varied depending upon the sizes of the sector-shaped pieces to be cut.
Still a further object of the present invention is to provide a transport system that has variable feed speeds for both sawing and carriage return.
These objects and many others will become fully apparent upon reading the specification to follow in conjunction with the attached drawings.